This Core will have facilities at three sites, the University of Texas at Austin (coordinating site), Indiana University School of Medicine in Indianapolis and the University of Colorado Health Sciences Center at Denver. Efforts at the Indiana site will be supported in part by a subcontract from UT Austin and activities at the Colorado site will be supported by funds available from sources other than the IMA. All three sites have made a considerable investment in gene array technology and the MA proposals benefit from this infrastructure. The overall goal is to use microarray technology to define changes in gene expression that either predict or accompany excessive alcohol consumption. This requires development and validation of arrays that can accurately measure levels of large numbers of RNAs from brain regions of both mice and rats. Of particular importance is reproducibility among sites for all steps of the array process, from tissue dissection to array data informatics. This will provide a measure of molecular neuroadaptation that will be comprehensive (analysis of a large number of brain genes) and consistent across projects. We will use both commercial (Affymetrix) and custom fabricated arrays to provide coverage of mouse, rat and drosophila genomes for NIA projects.